Hallmarks and Carats: How to Read the Marks on Gold Jewellery in Spain

Buying gold jewellery on the Costa del Sol is a pleasure: family run jewellers, artisan workshops and international boutiques sit a few steps from each other. But gold keeps a small secret worth knowing before you pay. Inside rings, on the clasp of chains or on the back of a pendant are tiny marks, the hallmarks. Knowing how to read them is the best guarantee that you are getting exactly what you were sold.

Also available in: Deutsch · Español

What a hallmark is

In Spain, articles made of precious metals are regulated by Law 17/1985 of 1 July and its implementing regulation, Royal Decree 197/1988. The rules set out two types of mark, struck into the piece with a punch:

• Mark of origin: identifies the registered manufacturer or importer. It is their signature.
• Guarantee mark: applied by an official assay laboratory after testing the metal, and showing the fineness of the alloy, that is, how much precious metal it contains.

Each metal has its own geometric shape in the guarantee mark, so gold, silver and platinum can be told apart with a loupe. The law provides exceptions for very small pieces, such as gold articles under three grams, which may be identified in another way.

Carats and thousandths: the same idea in two languages

Gold purity is expressed in two ways. Carats divide the metal into 24 parts; thousandths divide it into a thousand. On Spanish jewellery you will mostly see the figure in thousandths:

• 750: 18 carat gold, the standard for fine jewellery in Spain. Three quarters of it is pure gold.
• 585: 14 carat gold, common in imported pieces and some design collections.
• 375: 9 carat gold, harder and less expensive, frequent in the United Kingdom.
• 999: 24 carat gold, practically pure and too soft for most everyday jewellery.

For the other noble metals the most common figures are 950 for platinum and 925 for sterling silver.

A 750 inside a ring means that three quarters of its weight is pure gold: it is 18 carat gold.

What is not solid gold

Some terms sound similar and are not. Gold plated and gold vermeil mean a thin layer of gold over another metal; gold filled is thicker but is still not a solid piece. These are legitimate options for quality costume jewellery, as long as the seller says so clearly and the price reflects it. If a piece is sold as gold and carries no hallmarks, ask why before you decide.

How to check in the shop

1. Ask for a loupe. Any serious jeweller has one to hand and will not mind you looking at the marks.
2. Look for both marks. The maker’s mark and the guarantee mark with the fineness. Antique pieces may carry different historic marks.
3. Insist on a detailed invoice. It should state the metal, the fineness and the weight, and describe any stones.
4. Ask for a certificate for gems. For diamonds of a certain size, a certificate from an independent laboratory is standard.

Before selling or valuing

Hallmarks also matter when you want to sell a piece or inherit a collection. The fineness shown by the mark is the starting point of any valuation, although a professional buyer will always test the metal. For shopping ideas in Marbella, see our Marbella shopping guide.

A piece of gold jewellery is often a piece for life. Taking a minute to look at its marks is the most elegant way to begin that story.